Power line Communication (PLC) is a communication technology that uses power lines as its communication medium. Data travels over the same power line that provides electricity, thus allowing the existing power line infrastructure in homes, businesses or cars to be used for the purpose of transporting data without adding new wires. PLC technology is experiencing a period of rapid growth and finding its way into multiple applications and market segments including smart grid, lighting control, solar panel monitoring, energy metering, in-home video distribution, and electric cars. The global push for energy conservation is driving the need for intelligently communicating with energy generation and energy consuming devices. PLC offers a unique no-new-infrastructure approach to enabling rapid deployment of smart energy management technology around the world. Unlike wireless solutions, PLC does not have limitations of line-of-sight and short transmission range. PLC is also a cost-effective and easy-to-install technology for many applications.
Communication technologies may be used with PLC to provide high speed data transmission. Such communication technologies include packet-based communication technologies, such as ITU G.hn, HomePNA, HomePlug® AV and Multimedia over Coax Alliance (MoCA). Such communication technologies typically employ either Carrier-less Amplitude and Phase (CAP) modulation or discrete multi-tone (DMT) modulation. CAP modulation is a variation of quadrature amplitude modulation (QAM). CAP modulation produces the same form of signal as QAM without requiring in-phase and quadrature carrier components. DMT modulation is a modulation method in which the available bandwidth of a communication channel is divided into numerous orthogonal sub-channels. Sub-channel is also referred to as sub-carrier or tone. Each tone of a DMT communication system is capable of acting as a communications sub-channel that carries information between a transmitter and a receiver. Multicarrier systems that make use of DMT modulation may also be referred to as systems that employ Orthogonal Frequency Division Multiplexing (OFDM). OFDM is also the modulation method employed by many wireless communication technologies, including ITU G.hn, HomePlug® AV, MoCA, IEEE 802.11 and IEEE 802.16 (WiMAX). Technologies implementing DMT, OFDM and other multicarrier modulation schemes are generalized herein as being multicarrier systems.
Multicarrier systems enable high data rates to be achieved over wireless and wireline networks, as data may be separated and simultaneously sent over separate sub-channels operating at different frequencies. While simultaneously transmitting over multiple sub-channels greatly improves data throughput, the modulation technique may increase the power consumption of the transmitter and receiver. Efficiently managing power consumption of communication devices has become increasingly important as the devices become smaller and efficiencies of such devices become vital.